Method of making razor blades



March 1, 1932 R. E. THOMPSON 1,847,577

METHOD OF MAKING RAZOR BLADES Filed Nov. '20, 1930 3 Sheets-Sheet l March 1, 1932. R. E. THOMPSON 1,847,577

METHOD OF MAKING RAZQR BLADES Filed Nov. 20. 1930 3 Sheets-Sheet 2 .March 1, 1932. P N 1,847,577

I METHOD OF MAKING RAZOR BLADES Filed Nov. 20. 1930 3 Sheets-Sheet 3 VE/V 727a Patented Mar. 1, 1932 UNITED STATES PATENT OFFICE RALPH E. THOMPSON, OF BBOOKLINB, IASIAO'HUSMTS, ASIIGNOB TO 0mm:

SAFETY RAZOR COMPANY, OF BOSTON, IASSAOHUSETTB, A GJBZOBATION 0! DM- WARE lemon or name won. was

Application filed llovember 80, 1900. lerhl Io. 406,088.

This invention relates to improvements in the art-of making and distin ishing thin flexible razor blades having ifierent edge properties.

The extensive use into which safety razors have come in recent years has demonstrated that the same edge properties in blades are not best suited to all users; whereas the edge in a blade of hard temper may exactly meet the requirements of one user, an edge of softer and tougher property will be better suited for the next user, or where a delicate edge formed with a long bevel may fit the requirements of one case, a stouter edge formed with a more obtuse bevel will give greater satisfaction in the next.

In one of its aspects, the present invention consists in improvements in the art of making thin flexible razor blades which will make available for the first time to the public an assortment of interchangeable blades having different edge properties from which the user may make a choice in accordance with his experience, preference or whim. This is a new condition and a new possibility brought about, as already intimated, by the use and manufacture of safety razors and blades on a tremendous scale, and I believe I am the first to recognize this new development in the art and to take steps to satisfy its natural requirements through the medium of the present invention. I

The methods of making thin flexible razor d blades heretofore practiced involve a series of dependent steps designed to produce in great quantity blades of a single type having uniform edge properties. In another of its aspects, the present invention consists in a series of related steps which are diversified at appropriate points in the method so as to carry variously identified blades to difi'erent conclusions in respect to their edge properties. I prefer to modify the construction of each blade blank at the point of departure from the established routine so that it shall mechanically insure the correct selection for the particular series of steps designed for producing its particular edge properties, and at the same time, clearly marked and unmistakabl distinguished from all other blanks not su ected to or intended to be treated in the same series of steps.

The manner of thus modifying the blank construction and identifying the blanks whlch is best suited for the requirements of the case consists in end-notching them. The method of my invention, therefore, deals with a series of blanks distinguished from each other by having, for example, three notches, two notches, one notch or no notches formed n one or preferably both ends.

The mechanical function of these notches will be more fully understood and a preci ated from the detailed description of t e referred manner of practicing the meth of this invention. To illustrate, however, it may be said that at one point in the process the blanks are supplied to a number of rinding machines similar in appearance ut so ad usted in range as to impart different angles of bevel to the blanks presented to them respectively. These machines are equipped w1th magazines so related in their construction to the end notched blanks that only those blanks having the appropriate predetermined arrangement of end notches can be supplied n regular routine. Further, these machines are equipped with automatic feeding mechanism of such character that if a particular blank should be forced into the wrong magazine the feedin mechanism will fail to 'eliver it to the grinding mechanism, thus automatically selecting or discarding proper andimproper blanks. ()no object of my 1nvention is therefore the rovision of a method of so identifyin razor blade blanks by notchmg the ends t ereof that each blank after belng thus notched can be thereafter treated and finished only in a manner corresponding to the treatment assigned to blanks havin that particular identification.

y method of identifying the razor blade blan s not only serves its useful function during the manufacture or treatment of the blanks but also serves to identify the finished blades. The end notches furthermore not only provide a visual and permanent identi-- 50 I however, the blanks are notched in accordtion, the claims appended hereto being relied upon for that purpose.

Referring to the figures of the drawings:

Fig. 1 is a erspective view of a stack of blade blanks lieing end notched in accordance with my invention.

- Fig. 2 illustrates one of the blade blanks.

Fig. 3 is a fragmentary view of a stacking frame for holding blade blanks during the heat treatment thereof.

Figs. 4, 5 and 6 are fragmentary views of three blades having different cutting edge bevels.

Figs. 7, 8 and 9 are perspective views of three blades with diiferent edge characteristics and identified in accordance with my invention.

Fig. 10 is a perspective view of a magazine adapted to hold only blades end notched in the manner shown in Figs. 4 and 7 My invention contemplates the manufacture of safety razor blades having different edge characteristics to meet varying requirements and demands, and in accordance with my invention ll propose to accomplish this object by an improved method of manufacture. As illustrated and described herein I propose to have four difi'erent grades or characters of blades, the distinctions between the blades in these grades being particularly in the cutting edges thereof. he body portion of all the blades will in the normal use of my process be substantially the same, difiering only in a manner to visually and mechanically distinguish one from the other as hereinafter described. The initial blade blank used in manufacturing these blades will normally be the same regardless of the character of bladeto be produced and the initial step of stamping out the blanks is therefore the same for all blanks. Following this step ance with the character of blade it is desired to produce and in such manner that they can only pass through the treatin machines which will form the blanks into blades having edges corresponding to these desired characteristics. I

The first step of my improved process is the forming of the blade blanks 10, one of which is shown in Fig. 2, these blades being conimonly stamped out from sheet material. Fol.- lowing this operation certain of the blanks are notched, preferably in the ends thereof in accordance with the character of blade it is desired to produce. In describing my invention hereinI have made provision for four different rades or classes of blades, these different 0 asses being hereinafter referred to as classes 1, 2, 3 and 4. The blanks which are to be manufactured into blades of class 1 are not notched, their ends being left intact as in Fig. 2. The blanks which are to form blades of class 2 are provided with a single notch 12 in each end. The blanks which are to form blades of class 3 are rovided with two small notches 14 in each end? The blanks are to form blades of class 4 are provided with three notches 16 in each end. It will be noted that the notches 12 are deeper than the corresponding notches 16 and that the notches 14 are spaced diiferentl than are the corresponding notches 16. he purpose of such difference in size and spacing is to assure that each blank will be received only in apparatus or the blank holding magazine thereof which is adapted to give such treatment to the blank as to produce a blade corresponding to the particular class for which it is notched, all of which is hereinafter more particularly described.

Proceeding with the description of my process, the blanks 10 which are to form lades for class 2 are stacked within a holder 18 and secured in place therein by a binding screw 20, the holder being mounted on a; grinding machine table 22. This stack of blades is then subjected to the action of a grinding wheel 24 which forms the notches 12 therein. The-blanks 10 which are to form blades of classes 3 and 4 are treated in like manner but with grinding wheels to form notches 14 and 16 of the shape, size and location illustrated in Figs. 5, 6, 8 and 9. The blades are thereafter treated through the usual steps of hardening, drawing, grinding, honing and stropping to form the same into finished blades.

In accordance with my process certain apparati are provided for handling each class of blade. If the preliminary treatment or treatments of certain blade blanks of different classes are to be' the same the a arati therefor will be honstructed to take lilhdes of these different classes. Whenever and wherever in the process the treatment of blanks of different classes vary however, the blade handling apparati are so constructed that they will take r we only those blanks which have been notched in treatment.

After the-blanks are appropriatel notched: as illustrated in Fig. 1-, t eyarehar erred-and:- drawn to the. roper degree and for-thisrtreaty ment the blan s areisupported in stack formas,

tioninaholdensuchrasshownin Fig. 3.- 'Ihiat blank holders for these treatments will be so constructed as to hold all blanks regardless of the end-notching thereof. If however, the difi'erently notched blanks are to receive different heat treatments the holders therefor will be so constructed that the blanks will be received only in those holders in which they will receive the corresponding and proper treatment. For example, the holder shown in Fig. 3 is constructed to receive only those blanks provided with a single notch 12 in their ends. Other holders may in like manner be provided for receiving only those blanks corresponding to the other blade grades or classes.

Following the heat treatment the blades are sharpened, honed and stropped. The machines for performing these operations are provided wlth blade ma azines whereon'the blanks are held in stac ed formation and from which the blanks are taken individually as treated. One of these magazines which I have illustrated in Fig. 10 comprises a base 40, two relatively spaced pins 42 for engaging through the two outer apertures in the blanks and two further spaced studs 44 for engaging within the end notches 12. This magazine is adapted to receive only those blades which are end-notched at 12 as shown in Figs. 4 and 7 and will reject unnotched blades and blades notched as shown in Figs. 5, 6, 8 and 9. The sharpening, honing and stropping machines are constructed and adjusted to treat and form the blank edges in accordance with the different variationsrequired' in the different classes or grades of blades and the mounting of appropriate magazines on these varying machines mechanically and positively assures that only the proper blanks can be received and treated thereon. In accordance with m method of operation it is therefore impossible to make any error in treating the blanks through the various steps of their manufacture into blades.

In Figs. 4, 5 and 6 I have, for example, shown three blades of different edge bevel. The blade 50 of class 2 is provided with an obtuse bevel 52; the blade 54 of class 3 is provided with a sharper bevel 56; and the blade 58 of class 4 is provided with a still sharper and longer bevel 60. These different bevels are formed on different grinding machines in which the grinding tools are difi'erently adjusted to produce such bevels. The machines for producing the bevel 50 are provided with magazines like that shown in Fig. 10 which will receive only blanks of class 2. The machines for producing blanks 54 and 58 are in like manner provided with magazines which will respectively receive only blanks of classes 3 and 4. It is therefore impossible to grind blanks of each class in a machine other than one of the machines which is arranged to give the blank the bevel corresponding to its particular class.

Likewise, in honing and stropping the blades, it may be desirable to produce a class of blades wherein the edge is rather coarse, a class wherein the edge is relatively fine, and a class with an intermediate edge. The three blades shown in Figs. 7, 8 and 9 have their edges drawn in a greatly exaggerated manner to illustrate three such classes. The blade of class 2 is provided with relatively coarse edges 72, the blade 7 4 with intermediate edges 76, and the blade 78 with fine edges 80. These blades are end-notched at 12, 14 and 16 and the honing and stropping machines for producing the different edges 72, 76 and 80 are provided with magazines adapted to receive only blades correspondingly notched as shown in these figures. It will therefore be seen that the use of my method precludes and makes error in the production of different grades or classes of blade impossible.

I claim:

1. That improvement in the art of making safety razor blades having different edge properties, which consists in producing a quantity of blade blanks, variously notching portions of certain of the blanks to identify the blanks and conform them to fit only certain blade handling apparatus and thereafter treating the different notched blades with a diiferent combination of steps by mechanically handling them in apparati adapted only to take blades of a predetermined notched form.

2. That improvement in the art of making safety razor blades having different edge properties, which consists in producing a quantity of blade blanks, variously notching end portions of certain of the blanks to identify the blanks and conform them to fit only certain blado holding apparati and thereafter treating the differently notched blades with a diiferent combination of steps'by mechanically handling them in apparati adapt ed only to take blades of a predetermined notched form.

3. That improvement in the art of making .safety razor blades having different edge properties, which consists in dieing out from sheet stock a plurality of identical blade blanks, hardening and drawing to the same degree all of said blanks, end-notching certain only of the blanks, presenting all of the blanks to two differently adjusted grinding machines each having magazines designed to receive one kind of blank only, whereby the blanks are mechanically selected and ground to difierent edge bevels according as the blanks are notched or unnotched.

4,. That improvement in the art of making safety razor blades havingmdifierent edge, properties, which consists in ardeninf and drawing a plurality of identical blade b anks, 'end-notching certain only of the blanks, presenting all of the blanks to diflerently adjusted grinding machines having magazines with end guides correlatin the blanks according to their notches wit the adjustment of the machine.

5. That im rovement in the art of making safety razor lades, which consists in pronotched or notched in another manner.

Signed at Boston, Massachusetts, this 17th ducing a quantity of identical blanks, then performing the steps of hardening, drawing, grinding, honing and stropping said blanks, variously notchlng certain of the blanks at an intermediate point in such series of steps, and modifying each successlve ste microscopic edge pro erties in the blanks so notched as compare with the blanks unday of November, 1930.

RALPH E. THOMPSON.

rformed on those blanks to produce dlflerent I 

